Partek Genomics Suite (Partek Inc., St. Louis, MI) was used for the analysis of the normalized data. The differential expression level of a subset of genes selected from highly expressed genes by microarray was confirmed by quantitative real-time RT-PCR analysis. check details Isolated RNA was reverse transcribed and the resulting cDNA was then amplified using SYBR green and specific primers according to the manufacturer’s instructions (Applied Biosystems, Carlsbad, CA). All samples

were run in triplicate and the expression of each gene was standardized using the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a reference. Amplification reactions were performed using a 9700H real-time PCR instrument (Applied Biosystems, Carlsbad, CA). The conditions for the reactions were: 95 °C, 10 min; 95 °C, 15 s; 60 °C, 60 s for 40 cycles. The related genes expression was determined using 2−△△ct method. Data are expressed as mean ± SE. A one-way ANOVA determined whether the results had statistical significance. In some cases, a Student’s t-test was used for comparing the two groups. TNF-alpha inhibitor A P-value set at 0.05 was used to determine significant differences. All analyses were performed using SPSS 14.0 (IBM Corporation, Somers, NY). Xenograft tumor model mice implanted with HCT-116 human

colorectal carcinoma cells were administrated with 25 and 50 mg/kg PPD. After 30 days of treatment, 25 and 50 mg/kg PPD inhibited tumor growth approximately by 35% and 50%, respectively ( Fig. 2:

A and B; P < 0.01 compared to control, P < 0.05, compared to 25 mg/kg group). With the assistance of veterinary staff in the animal care facility mafosfamide in our university, no obvious clinical signs of adverse events were observed during the PPD treatment. These daily observations included: motor activity (locomotion, catalepsy), respiration (dyspnea), skin (edema, erythema), and reflexes (light) (17). Growth inhibitory effects of PPD on SW-480, HT-29, and HCT-116 cancer cells at various PPD concentrations (5, 10, 20, 30 and 40 μM) were evaluated at 24, 48 or 72 h. The MTS assay results are shown in Fig. 3A, B and C. The growth of the treated cells decreased significantly in a concentration-dependent manner. We also observed that, PPD at 20 μM, HCT-116 cells were significantly more sensitive to the treatment than the other two cells, suggesting that the status of p53 could account for this difference. A normal rat small intestine epithelial cell line, IEC-6, was used to evaluate the effects of PPD. Compared with the control (100%), the cell viabilities of PPD on IEC-6 cells in 10, 20, 30 and 40 μM for 48 h were 100.8 ± 5.0%, 103.5 ± 4.8%, 101.4 ± 7.3%, and 86.3 ± 6.6%, respectively. In contrast, cell growth was almost totally inhibited in all the three colorectal cancer cell lines when treated with PPD at 30 μM (Fig. 3). HCT-116 and SW-480 cells were treated with different PPD concentrations (15, 20, 25, 30, and 35 μM) for 72 h.